Prevalence and screening of exon 4 of the Interleukin-4 gene in Ascaris lumbricoides infected patients from district Mardan, Pakistan

Abstract

Background: A. lumbricoides, commonly known as the large intestinal roundworm, is one of the most prevalent parasitic worms infecting humans worldwide. These pale, cylindrical worms can grow up to 35 centimeters in length and primarily infest the human small intestine. This nematode is thought to affect 25 percent of the world's population. The purpose of this study is to investigate the prevalence, morphology and screening of exon 4 of the interleukin-4 gene in district Mardan, Khyber Pakhtunkhwa, Pakistan. Methodology: The cross-sectional study involved the collection of prevalence data, worms and blood samples from Ascaris-infected patients. Worm marphometry was performed using a ruler, balance scale, and vernier caliper. DNA was extracted from blood samples using the phenol-chloroform method. Exon-4 of the IL-4 gene was amplified using PCR. Agarose gel electrophoresis was used to validate the PCR results. Chi-square was used to find the association of infection with demographic, environmental and clinical risk factors. Results: The diameter of the worm ranges from 3–6.25 mm, the length is 12.9–32.8 cm, and the weight of the worm ranges from 0.47 g to 4.485 g. Among 265 individuals, the prevalence rate was 20%%. The prevalence rate in males was 37 (13.96%), while in females it was 16 (6.03%). Among age groups, the highest prevalence was seen in the age group 1–10 years, which accounts for 33 (12.45%) (p = 0.052). This result showed no significant association with infection. People living in village 50 (18.86%), lower class 42 (15.84%; p = 0.009*), poor status of living 44 (16.60%; (p = 0.001*), and people working as labor had 26 (9.81%; p = 0.013*) significantly associated with infection. People with no or primary education have the highest recorded prevalence rate, which is 21 (7.92%) (P = 0.128). The risk factors associated with the prevalence were wearing footwear 44 (16.60%) (p = 0.04*), standing water ponds 36 (13.58%) (p = 0.002), having no washroom 27 (10.18%) (p = 0.000*), and people defecating in open fields 42 (15.84%) (p = 0.011) were significantly associated with infection. Washing hands before meals, the presence of grass and bushes, drinking water, using waste as fertilizer, sewage water merging with running water, condition of living and washing hands after defecation (p > 0.05) did not show any significant relationship with the risk of infection. People who had never been treated with anti-helminthic drugs have the 5 | P a g e highest prevalence, which is 43 (16.22%), as in those who were previously dewormed (p = 0.007). The most effective drug during this study was Albendazole, whose effectiveness was the highest at 12.07%, followed by piperazine which has 3.01%. Other anti-helminthic drugs show less effect against the Ascaris worm. DNA samples from people with A. lumbricoides infections were amplified using the Polymerase Chain Reaction (PCR). The IL-4 gene (exon 4) 559 bp long PCR amplified product was obtained. Conclusion: The study illustrates a number of factors associated with A. lumbricoides transmission, including poor living, environmental conditions, a lack of washrooms, and open-field defecation, which are major contributors to prevalence. Above all, stress and reaffirm that acute poverty and A. lumbricoides infection are inevitably linked. Improving hygiene conditions and habits is essential to reduce the risk of A. lumbricoides.